Paper machinery



5; 1969 w. c. NOTBOHM 31,459,124

PAPER MACHINERY Fliled Oct. 20, 1966 FIG2 I2 II H ' INVENTOR.

WILLARD C. NOTBOHM ATTORNEYS United States Patent 3,459,124 PAPER MACHINERY Willard C. Notbohm, Watertown, N.Y., assignor to The Black Clawson Company, Hamilton, Ohio, a corporation of Ohio Filed Oct. 20, 1966, Ser. No. 588,041 Int. Cl. 1330b /16, 3/04 US. Cl. 100-170 4 Claims ABSTRACT OF THE DISCLOSURE This invention relates to paper making machinery, and more particularly to multiple roll stacks used in the manufacture of paper, such as press sections.

The invention was developed primarily in conjunction with three-roll press sections comprising a pair of press rolls of conventional construction and size having an imperforate roll of relatively much smaller diameter positioned therebetween and in nip-forming relation with both thereof, reference being made in this connection to Patent No. 3,331,734 and assigned to the same assignee. The invention has special relation to the positioning of the intermediate roll in such three-roll press or other threeroll stack.

It has been found in the use of three-roll presses of the type just described that optimum operating conditions are obtained when the intermediate roll is offset laterally with respect to the plane defined by the axes of the outer pair of rolls, and particularly when the offset relation of the intermeditae roll is such that the compressive and torsional forces effective thereon are substantially balanced. Similar conditions obtained in other multiple roll stacks such as calendars, is explained in greater detail in Patent No. 3,331,313 also and assigned to the same assignee.

It is a primary object of the present invention to provide a novel fluid control system for use in conjunction with multiple roll stacks of the type just described to establish accurate balancing of the lateral components of the torsional and comprehensive forces acting on the intermediate roll of a three-roll couple.

A more specific object of the invention is to provide a control system as outlined above which is capable of precisely sensing the magnitude and direction of the resultant lateral force on the intermediate roll and of giving a direct positive indication of the same, and also to provide a system having such sensing and indicating propertites which incorporates an adjusting mechanism for quickly and accurately correcting departure of either end of the intermediate roll from its optimum relationship with the two adjacent rolls.

Another specific object of the invention is to provide a control system as outlined above which includes a closed hydraulic circuit having such operative connections with the two ends of the intermediate roll as to produce the desired accurate sensing and indication of the resultant lateral force on the intermediate roll.

Additional objects and advantages of the invention will be apparent from the following description, the accompanying drawing and the appended claims.

3,459,124 Patented Aug. 5, 1969 "ice In the drawing FIG. 1 is a diagrammatic view illustrating a paper machine press section constructed in accordance with the invention;

FIG. 2 is a fragmentary view of an end portion of the press section taken generally along the line 2-2 of FIG. 1;

FIG. 3 is a fragmentary view of the same end portion of the press section of FIG. 2 taken generally along the line 33 of FIG. 1;

FIG. 4 is an enlarged detail view of the mechanism for supporting one end of the intermediate roll in accordance with the invention;

FIG. 5 is a view in part section of the support mechanism taken generally along the line 5-5 of FIG. 4; and

FIG. 6 is a schematic diagram of a fluid sensing and indicating system assembly in accordance with the invention.

Referring to the drawing, which illustrates a preferred embodiment of the invention, a force balancing system constructed in accordance with the invention is shown in use on a high intensity press section of a paper machine of the general type disclosed in the above noted Patent No. 3,331,734. While only one side of the press section is shown, it is understood that the same construction is duplicated at the opposite side of the press.

In general, the press section includes a frame 10 which rotatably supports a large diameter press roll 11 having journals 12. An intermediate roll 13 having a substantially smaller diameter and including journals 15 (FIG. 3), forms a nip with the press roll 11. The frame 10 also rotatably supports a large diameter backup roll 16 having journals 17 so that the roll 16 forms a nip with the intermediate roll 13 generally opposite the nip formed with the press roll 11. A web W of paper is carried by an endless felt F through the nip formed between the press roll 11 and intermediate roll 13 so that moisture is squeezed from the combined web and felt by the high intensity nip pressure produced between the intermediate roll 13 and the press roll 11.

As illustrated in FIG. 1, the backup roll 16 is driven counterclockwise by a suitable drive 19 and the press roll 11 may be provided with a helper drive 21, especially for starting purposes. As also shown in FIG. 1, the intermediate roll 13 is positioned slightly offset relative to a plane 22 defined by the axes of the journals 15 and 17 so that the lateral inward force component produced by the torque transmitted to the intermediate roll 13 from the backup roll 16 is opposed by the lateral outward force component produced by the compression of the intermediate roll 13 between the rolls 11 and 16.

A hydraulic pressure cylinder 25 including a piston rod 26 extending from a piston 28 (FIG. 6), is connected to the end portion of each of the intermediate roll journals 15 by a member 30 threadably mounted on the end of the piston rod 26. Each member 30 is provided with a counterbore 32 for retaining a bearing (not shown) which rotatably supports the associated journal 15. An L-shaped flange 34 (FIG. 3) projects from the member 30 and is normally spaced slightly above a support bracket 35 mounted on the frame 10. A nut 36 is threaded on the opposite end of the piston rod 26 for limiting the stroke of the rod.

The hydraulic cylinder 25 has a relatively high pressure rating, as for example, from between 2000 to 3000 p.s.i., and is provided with a pressure chamber 38 (FIG. 6) on each end of the piston 28. The cylinder 25 is pivotally supported by a member 40 (FIG. 5) including a pair of plates 42 spaced apart by a block 43. Aligned holes 44 are formed Within the plates 42 for receiving corresponding aligned stub shafts 45 (FIG. 5) projecting from opposite sides of the hydraulic cylinder 25. The

plates 42 are rigidly secured to the block by a pair of bolts 47 and are provided with opposing slots or grooves 48 for slidably receiving a guide plate 50 rigidly secured to the frame.

A threaded hole 52 is formed within the block 43 and receives a lead screw 54 extending through a plate 55 rigidly mounted on the frame 10. A pair of nuts 57 are pinned to the screw 54 on opposite sides of the plates 55 to prevent axial movement of the screw 54. A square shank 59 is formed on the end of the lead screw 54, and when the lead screw 54 is rotated by use of awrench 60 engaging the shank 59, the member 40 and the cylinder along with the intermediate roll 13 are moved in a lateral direction generally normal to the plane 22 defined by the axes of the press roll 11 and backup roll 16. A scale 61 is provided on the outer plate 42 for indicating the lateral position of the intermediate roll 13 by reference with a pointer 62 provided on the frame 10.

By further rotating the lead screw 54 in one direction, the intermediate roll 13 can be moved out of its nip forming relationship with the press roll 11 and backup roll 16, at which time the flange 34 of the bearing retaining member is picked up by the bracket 35. It can be seen that the pivotable support of the cylinder 25 by the plates 42 enables the intermediate roll 13 to float between the press roll 11 and backup roll 16 so that the nip pressure with each roll is equalized and there is no torque transmitted to the support member 30 from the intermediate roll 13.

Referring to FIG. 6, the pressure chamber 38 on each side of the piston 28 within the hydraulic cylinder 25 is connected to one of a pair of pressure gauges 65 by a conduit 66. In addition, the cylinder 25 is provided with a fitting 68 for each chamber 38 by which suitable hydraulic fluid is loaded and sealed into the chambers.

In operation, the piston 28 within the hydraulic cylinder 25 is preloaded by filling the chambers 38 with hydraulic fluid through the fittings 68 until each gauge reads substantially the same predetermined pressure. This is readily done as the final operation of fabricating the cylinder before it is assembled on the press, and satisfactory results are obtained using a heavy-bodied lubricant such as grease. After the press roll 11 and backup roll 16 are brought up to speed and the press section is in operation, if the pressure indicated by one of the gauges 65 decreases and the other gauge increases, this indicates that the lateral forces acting on the intermediate roll 13 are unbalanced and that an adjustment of this roll is desirable. The opposing lateral forces acting on the roll 13 are then rebalanced by rotating the lead screw 54 with the wrench 60 until both gauges 65 read the same pressure.

In summary, the fluid operated system for balancing the opposing lateral force components on the intermediate roll 13 provides several desirable features and advantages. The system not only provides a positive and direct indication of the magnitude of the unbalanced lateral force, but it also indicates the direction in which the intermediate roll should be moved for rebalancing the lateral forces. Furthermore, it has been found that by observing the gauges during lateral adjustment of the intermediate roll 13, the roll can be precisely positioned without a trial and error procedure.

Additional advantages are that the hydraulic system of the invention provides a dependable indication and control and is also economical in construction. It is to be understood, however, that if it is desirable to provide for automatic balancing of the lateral forces, the fluid pressure within the cylinders 25 could be sensed with commercially available pressure sensing devices which, in turn, could operate a reversible drive motor connected to the adjusting lead screw 54. It will also be apparent that although the invention has been described in con- .4 nection with a three-roll press wherein the intermediate roll is of much smaller diameter than the outer pair of rolls, its principles are applicable to other types of multiple roll stacks and couples, including a paper machine calendar of the characteristics disclosed in the above noted Patent No. 3,331,313.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that the changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. In a multiple roll stack including two parallel spaced rolls each in nip forming relationship with an intermediate roll positioned to intersect a plane defined by the axes of said spaced rolls, and including means for driving at least one of said rolls, an improved system for balancing the lateral forces acting on said intermediate roll by the other two said rolls to minimize wear on said intermediate roll and for obtaining uniform nip pressure, comprising a hydraulic pressure cylinder for each end of said intermediate roll and including means defining a chamber therein, each said cylinder including a piston mounted within the corresponding said chamber and connected by a piston rod extending generally normal to said plane to the corresponding end of said intermediate roll so that pressure within each said cylinder chamber changes in response to changes in the lateral forces acting on the corresponding end of said intermediate roll, means for sensing the fluid pressure within each said cylinder chamber to determine the magnitude and direction of the resultant of said lateral forces, a track for each said cylinder and extending generally normal to said plane, a bracket movably mounted on each said truck and supporting the corresponding said cylinder for axial movement, and adjusting means for moving each said bracket and the corresponding said cylinder on the corresponding said track for laterally positioning each end of said intermediate roll in accordance with the pressure sensed within said chamber.

2. The combination defined in claim 1 wherein said intermediate roll is substantially smaller in diameter than said spaced rolls for producing a high intensity nip pressure.

3. The combination defined in claim 1 including means pivotally connecting each said pressure cylinder to the corresponding said bracket to provide for floating movement of said intermediate roll generally within said plane defined by the axes of said spaced rolls.

4. The combination defined in claim 1 including means associated with each hydraulic cylinder and independent of said track for supporting said intermediate roll when it is moved laterally to a position out of nip relation with said spaced rolls.

References Cited UNITED STATES PATENTS 1,772,188 8/1930 Mason -99 X 2,364,443 12/1944 Hornbostel 100-168 3,044,392 7/1962 Minarik 100-162 3,066,876 12/1962 Verdier 100-161 X 3,306,814 2/1967 McHugh 162-361 X 3,331,313 7/1967 Notbohm et a1. 100-162 X FOREIGN PATENTS 7,992 3/1911 Great Britain.

PETER FELDMAN, Primary Examiner US. Cl. X.R. 

